含硫液体烃燃料水蒸气重整制氢Ⅰ. Pt/Ce0.8Gd0.2O1.9催化剂的制备、表征和抗硫性能

 以柠檬酸溶胶-凝胶法合成的具有萤石结构的Ce0.8Gd0.2O1.9(CGO)复合氧化物为载体,用初湿浸润法制备了负载型Pt催化剂. 纯异辛烷的重整反应结果显示, 600和800 ℃焙烧的催化剂达到了热力学平衡转化, 1000 ℃焙烧会导致Pt的聚集和氧化物的严重烧结,因而催化剂活性较差. 抗硫测试表明, 800 ℃焙烧的催化剂抗硫性能最好,在300 μg/g硫存在下, 100 h内异辛烷均接近完全转化; 在500 μg/g硫存在下催化剂仍表现出良好抗硫性能. 程序升温还原和X射线分析结果显示, 800 ℃焙烧时Pt与CGO载体间的相互作用最强,同时催化剂具有良好的热稳定性,这是催化剂具有抗硫性能并且抗硫作用持久的根本原因. 反应条件下噻吩硫完全转化成H2S, 硫的转化可能是通过氧化-还原机理进行的.     

含硫液体烃燃料水蒸气重整制氢I．Pt／Ce0．8Gd0．2O1．9催化剂的制备、表征和抗硫性能

以柠檬酸溶胶-凝胶法合成的具有萤石结构的Ce0.8Gd0.2O1.9（CGO）复合氧化物为载体，用初湿浸润法制备了负载型Pt催化剂．纯异辛烷的重整反应结果显示，600和800℃焙烧的催化剂达到了热力学平衡转化，1000℃焙烧会导致Pt的聚集和氧化物的严重烧结，因而催化剂活性较差．抗硫测试表明，800℃焙烧的催化剂抗硫性能最好，在300μg／g硫存在下，100h内异辛烷均接近完全转化；在500μg／g硫存在下催化剂仍表现出良好抗硫性能．程序升温还原和X射线分析结果显示．800℃焙烧时Pt与CGO载体间的相互作用最强，同时催化剂具有良好的热稳定性，这是催化剂具有抗硫性能并且抗硫作用持久的根本原因．反应条件下噻吩硫完全转化成H2S，硫的转化可能是通过氧化-还原机理进行的．     

多壁碳纳米管负载高分散Pt-PrxCe1-xO2-δ复合催化剂对甲醇的电催化氧化作用研究

通过反向化学共沉淀法制备PrxCe1-xO2-δ稀土纳米复合氧化物作为助催化掺杂剂,将其包覆在多壁碳纳米管(MWCNTs)的表面作为催化剂复合载体,然后使用了柠檬酸盐-KBH4液相还原法制备了粒径分布均匀、性质稳定的Pt纳米溶胶,并沉积在上述载体中得到负载型Pt-PrxCe1-xO2-δ/CNT复合电催化剂,制备的催化剂中Pt载量为20%(质量分数).使用XRD,SEM等手段对催化剂样品进行了物相形貌表征.使用循环伏安法对催化剂的电化学性能进行了测试.结果表明,经Pr,Ce纳米复合氧化物掺杂的催化剂比传统Pt/CNT催化荆具有更低的甲醇氧化电位和更好的耐中间产物毒化能力.     

铝基类水滑石和复合氧化物负载Pt催化剂的制备及对甲基苯酚加氢脱氧反应的催化性能

采用共沉淀法制备了多种铝基类水滑石,焙烧后得到对应的复合氧化物;以水滑石或复合氧化物为载体,制备了系列Pt基催化剂,研究了该催化剂对甲基苯酚加氢脱氧反应的催化性能。结果表明,Pt基催化剂的性能与载体的组分组成和结构相关;当以不经焙烧的类水滑石做载体时,所制备的Pt基催化剂具有较高的活性。其中,Pt-Ni-Al-H催化剂的加氢脱氧活性最高,对甲基苯酚转化率达到99.8%,甲苯选择性为1.4%,而Pt-Zn-Al-H催化剂的直接脱氧活性最高,在275℃和氢压2MPa下反应1h后,甲苯选择性达到84.1%。研究发现,反应过程中所生成的甲基环己烷可进一步发生脱氢反应转化为甲苯,说明所制备的Pt基催化剂具有较好的脱氢活性,可节省脱氧过程中的氢气消耗量。     

Ce-Zr-O固溶体的制备和表征

采用硝酸盐直接分解法、共沉淀法、苹果酸溶胶 凝胶法和柠檬酸溶胶 凝胶法制备了Ce Zr O复合氧化物并进行了表征。溶胶 凝胶法制得的Ce Zr O为立方的Ce0 .5Zr0 .5O2 复合氧化物 (其中少量具有立方性质的t″相 ) ,而直接分解和共沉淀法制得的是由立方Ce0 .8Zr0 .2 O2 和四方Ce0 .2 Zr0 .8O2 固溶体组成的复合氧化物。不同制备方法制得的样品由于物相组成不同 ,还原性能也有较大差别。差热分析和X射线衍射分析结果表明 ,凝胶在燃烧的同时生成了Ce0 .5Zr0 .5O2 固溶体。     

铝基类水滑石和复合氧化物负载Pt催化剂的制备及对甲基苯酚加氢脱氧反应的催化性能（英文）

采用共沉淀法制备了多种铝基类水滑石,焙烧后得到对应的复合氧化物;以水滑石或复合氧化物为载体,制备了系列Pt基催化剂,研究了该催化剂对甲基苯酚加氢脱氧反应的催化性能。结果表明,Pt基催化剂的性能与载体的组分组成和结构相关;当以不经焙烧的类水滑石做载体时,所制备的Pt基催化剂具有较高的活性。其中,Pt-Ni-Al-H催化剂的加氢脱氧活性最高,对甲基苯酚转化率达到99.8%,甲苯选择性为1.4%,而Pt-Zn-Al-H催化剂的直接脱氧活性最高,在275℃和氢压2 MPa下反应1 h后,甲苯选择性达到84.1%。研究发现,反应过程中所生成的甲基环己烷可进一步发生脱氢反应转化为甲苯,说明所制备的Pt基催化剂具有较好的脱氢活性,可节省脱氧过程中的氢气消耗量。     

Ce—Zr—固溶体的制备和表征

采用硝酸盐直接分解法、共沉淀法、苹果酸溶胶、凝胶 柠檬酸溶胶－凝胶法制备了Ｃｅ－Ｚｒ－Ｏ复合氧化物并进行了表征。溶胶－凝胶法制得的Ｃｅ－Ｚｒ－Ｏ为立方的Ｃｅ０．５Ｚｒ０．５Ｏ２复合氧化物（其中少量具有立方性质的ｔ＾〃相）,而直接分解和共沉淀法制得的是由立方Ｃｅ０．８Ｚｒ０．２Ｏ２和四方Ｃｅ０．２Ｚｒ０．８Ｏ２固溶体组成的复合氧化物。不同制备方法制得的样品由于物相组成不同,还原性能也有较大差别。差热     

草酸盐凝胶共沉淀法制备Ni-Ce-O甲烷催化燃烧催化剂

 采用草酸盐凝胶共沉淀法制备了系列Ni-Ce-O复合氧化物催化剂,考察了制备方法及催化剂组成对其催化甲烷燃烧性能的影响. 结果表明,草酸盐凝胶共沉淀法制备的Ni-Ce-O催化剂上甲烷的催化燃烧活性明显高于常规方法制备的Ni-Ce-O催化剂; Ni-Ce-O催化剂的组成显著影响其催化性能. 当镍/铈比值为4时,在406 ℃时即可使50%甲烷转化. Ni-Ce-O复合氧化物中NiO的晶格微应变是影响其催化甲烷燃烧性能的重要因素.     

非均相催化一步合成碳酸二苯酯的研究 I．载体制备方法对催化剂性能的影响

采用溶胶－凝胶法、共沉淀法和冷冻干燥法，制备了LaxMnyPbzO复合型氧化物载体，并以PbCl2或Na2PbCl4的水溶液为浸渍液，通过浸渍方法制固相催化剂，用于一步俣成碳酸二苯酯，用XRD，TEM及SEM对载体及催化剂进行了表征，结果表明，三种载体的主要物相皆为La0.3Mn0.5PbO，溶胶－凝胶法制得的载体及催化剂的粒径分布较好，空隙率较大，活性组分分散度较高；溶胶－凝胶法制得的催化剂的催化性能较好，碳酸二苯酯选择属于选择性可高于99．5％。     

制备方法对La_(0.7)Ce_(0.3)Ni_(0.7)Fe_(0.3)O_3催化性能的影响

以聚苯乙烯胶晶为模板剂,分别用溶胶-凝胶法、共沉淀法和水热合成法制备La_(0.7)Ce_(0.3)Ni_(0.7)Fe_(0.3)O_3钙钛矿复合氧化物,利用XRD, H_2-TPR, SEM, N_2-吸附脱附和FT-IR等对钙钛矿复合氧化物的结构和物化性能进行了表征。同时以乙醇水蒸气重整为探针,考察了催化剂的活性及抗积碳性能。结果表明:溶胶凝胶制备的La_(0.7)Ce_(0.3)Ni_(0.7)Fe_(0.3)O_3复合氧化物表面结构疏松,具有较大的比表面积和适宜的孔径分布,在还原过程中产生较多的金属活性中心,在400℃时乙醇转化率可达到100%,且具有较好的抗积碳性能。     

利用手持技术改进测定乙醇分子结构实验

利用压强传感器代替排水集气法,改进测定乙醇分子结构实验的仪器装置,并探索最佳反应条件。另外,设计两个空白实验,结合压强变化曲线对实验误差进行相关讨论。     

非那雄胺合成工艺改进

非那雄胺能抑制5α-还原酶的活性,明显降低二氢睾酮水平,是一种治疗良性前列腺增生的有效药品。该合成工艺以甾烯酮酸为原料,将其与氯化亚砜反应,无须分离即与叔丁胺反应得17β-酰胺化合物,再氧化开环,环合,氢化,脱氢合成了非那雄胺。经元素分析、IR、1HNMR、13CNMR、MS分析表征了其结构。该法无须使用昂贵的2,2-二吡啶二硫化物和剧毒药品苯亚硒酸酐,且以乙酸铵代替氨气,降低了对设备的要求和腐蚀,更适用于工业生产。     

Calculation of enthalpies of hydrogenation of hydrocarbons

Sets of hydrogen molecule equivalents have been developed which permit the calculation of hydrogenation of different types of carbon-carbon bonds from ab initio total energies (3-21G and 6-31G* basis sets, and, to a more limited extent, for MP2/6-31G* data) of reactants and products. The calculated enthalpies of hydrogenation are in good agreement with experiment for unstrained molecules, with average errors on the order of 2 kcal/mol. The 6-31G* equivalents allow the enthalpies for strained molecules to be calculated accurately, but the 3-21G equivalents do not. The equivalents for both basis sets have been tested by calculating the enthalpies of hydrogenation of carbon-carbon bonds in nitrogen- and oxygen-containing organic molecules, free radicals, and classical carbocations. The results are in good agreement with experiment in most cases.     

光谱仪测试范围的扩展

由于石化行业的生产需要，其材质的使用具有多样性和广泛性，经常会出现顾客委托的测试样品的一个或几个元素跨越光谱仪现有测试程序测量范围的情况。本法通过对光谱仪测试原理的认识，根据光谱仪的测试能力及标样的采集，实现了一个或几个元素测量范围的扩展，并对其测量的影响因素进行了研究。     

Neutral diterpenoids of oleoresins of five species of conifers of Transcarpathia

The compositions of the neutral diterpenoids of the oleoresins of five species of conifers growing in the Transcarpathia have been studied. It has been found that the oleoresins ofAbies alba M.,Larix decidua M., andPicea excelsa L. contain more than 50% of neutral diterpenoids. The group and qualitative compositions of the oxygen-containing diterpenoids have been determined. In the oleoresins ofAbies alba,Picea excelsa, andPicea abies tertiary alcohols — cis-abienol and isocembrol — predominate, while inLarix decidua the main component is the hydroxy ester larixyl acetate. Primary alcohols related to the resin acids have been found in all the oleoresins investigated. Features of the distribution of diterpenoids according to the species of conifers have been revealed. The results obtained are necessary for the chemotaxonomy of conifers of the family Pinceae.Novosibirsk Institute of Organic Chemistry, Siberian Branch, Academy of Sciences of the USSR. Translated from Khimiya Prirodynkh Soedinenii, No. 6, pp. 812–816, November–December, 1988.     

Neutral diterpenoids of oleoresins of five species of conifers of Transcarpathia

The compositions of the neutral diterpenoids of the oleoresins of five species of conifers growing in the Transcarpathia have been studied. It has been found that the oleoresins ofAbies alba M.,Larix decidua M., andPicea excelsa L. contain more than 50% of neutral diterpenoids. The group and qualitative compositions of the oxygen-containing diterpenoids have been determined. In the oleoresins ofAbies alba,Picea excelsa, andPicea abies tertiary alcohols — cis-abienol and isocembrol — predominate, while inLarix decidua the main component is the hydroxy ester larixyl acetate. Primary alcohols related to the resin acids have been found in all the oleoresins investigated. Features of the distribution of diterpenoids according to the species of conifers have been revealed. The results obtained are necessary for the chemotaxonomy of conifers of the family Pinceae.     

Influence of viscosity of medium on processes of oxygen quenching of excited states of mesoporphyrin

The oxygen quenching rate constants for singlet and triplet excited states of the dimethyl ester of mesoporphyrin IX increase with decreasing viscosity of the medium and reach a maximum at a viscosity of approximately 0.4 mPa·sec, after which the rate constants begin to decrease. The drop in rate constant with increasing fluidity of the medium may be related to a nonequilibrium character of the elementary act in the interaction of the reactants in the solvent cage. In viscous media such as isopropyl alcohol, isobutyl alcohol, and isoamyl alcohol, the reaction radius is greater than the sum of the radii of the reacting particles. The long-range character of these processes is due to the relatively weak dependence of the quenching probability on distance.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 25, No. 2, pp. 161–167, March–April, 1989.     

Dichroism of absorption and polarization of phosphorescence of molecules of the closed form of nitrobenzospirothiopyran

The spectral-polarization characteristics of absorption and phosphorescence of molecules of the initial form of nitro-substituted indolinospirobenzothiopyran were studied in oriented polyethylene films and in solutions with different polarity. An oscillator model of the electron transitions responsible for the formation of absorption and luminescence spectra was suggested. It was established that the principal differences in the spectral and photophysical properties of the compound studied and its oxygen-containing analog are associated with the fact that the electronegativity of the S atom is lower than that of the O atom. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1143–1146, June, 1997.